1. Field of the Invention
The present invention relates to an electronic device which includes a liquid crystal display unit.
2. Description of the Related Art
When a liquid crystal display unit is mounted in an electronic device such as a digital camera, a light emitting unit is necessary for providing backlight to the liquid crystal display unit. A light emitting diode (LED) has been used as a light emitting unit. Japanese Patent Application Laid-open No. 2007-220855 discusses an LED lighting circuit that includes a plurality of light emitting units for providing backlight to a liquid crystal display unit.
The LED lighting circuit discussed in Japanese Patent Application Laid-open No, 2007-220855 has a direct current (DC)-DC converter for controlling an output voltage of a power source.
However, the DC-DC converter discussed in Japanese Patent Application Laid-open No. 2007-220855 can generate a voltage necessary for the light emitting unit from the output voltage of the power source but cannot generate a voltage necessary for a circuit other than the light emitting unit from the output voltage of the power source. Therefore, the DC-DC converter discussed in Japanese Patent Application Laid-open No. 2007-220855 cannot he used as a DC-DC converter, for a configuration element other than the light emitting unit (for example, a communication unit configured to transmit video data).